Bifurcation of the portal vein appearing as a focal defect on the liver image.

A focal defect was seen on a gamma camera image of the liver in 2 patients, a 52-year-old woman with abdominal pain and a 46-year-old woman with pancytopenia. Liver function was normal, and no tumor stain was seen. Angiography revealed that the "defect" was in reality the bifurcation of the portal vein. These findings re-emphasize the importance of visceral angiography as a complement to radionuclide imaging in the study of liver disease.